function meetSb(url_in) {
	alert(url_in);
	sendCometAjax(url_in, {
		methodName : 'meetsomebody'
	}, null, function(sbName) {
		if (sbName != null) {
			alert('you can talk with ' + sbName
					+ ' now,enjoy your conversation!');
		} else {
			alert('sorry, there is no one online!');
		}

	});
}